Metabolism of i.v. administered 45 kDa epidermal growth factor in the rat.
The 45 kDa epidermal growth factor (EGF-(45 kDa)) has been purified from rat urine. We have investigated the distribution and the processing of i.v. injected 125I-labeled EGF-(45 kDa) in the rat. 2.5 min after the i.v. injection only 12% of the label remained in the blood. Most of the label was found in the liver (54%), in the kidneys (7%) and in the skin (4%). The submandibular glands, stomach, small intestine, colon, spleen and lungs contained 1% or less of the radioactivity. Some of the 125I-EGF-(45 kDa) was processed to 125I-EGF-(6 kDa) immunoreactivity in the liver and in the kidneys. The kidneys excreted 125I-EGF-(45 kDa) in the urine, but we were not able to demonstrate 125I-EGF-(6 kDa) in urine. In conclusion, this study shows that homologous EGF-(45 kDa) is cleared from the circulation of rats within a few minutes, mainly by the liver and the kidneys. In vivo both the liver and the kidneys are able to process some of the EGF-(45 kDa) to EGF-(6 kDa) immunoreactivity.
Jørgensen
P E
PE
Department B, University of Copenhagen, Denmark.
Nexø
E
E
Raaberg
L
L
Rasmussen
T N
TN
Poulsen
S S
SS
D000818:Animals; D004815:Epidermal Growth Factor / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism*; D007275:Injections, Intravenous; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D008970:Molecular Weight; D011498:Protein Precursors / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012867:Skin / Q000378:metabolism; D014018:Tissue Distribution
D011498:Protein Precursors; D004815:Epidermal Growth Factor